Proteomic profiling reveals candidate biomarkers of ovarian inactivity in yak via Astral-DIA

Abstract

Inactive ovaries are one of the major causes of low reproductive performance in yaks, but their underlying molecular mechanisms remain unclear. In this study, we applied the high‑throughput and high‑sensitivity Astral‑DIA (Data‑Independent Acquisition) technique to identify differentially expressed proteins in ovarian tissues from yaks with inactive ovaries (IO) compared to those in natural estrus (ECG). A total of 165 highly significant differentially expressed proteins were identified, including 87 upregulated and 78 downregulated proteins. Gene Ontology (GO), EggNOG functional classification, KEGG pathway analysis, and subcellular localization prediction were performed to annotate and characterize these proteins. Protein–protein interaction (PPI) network analysis revealed five representative differential proteins—MAO, FSTL3, HAPLN1, PTGFR, and RDH11—as potential key regulators of ovarian activity. Western blot validation confirmed the consistency of the proteomic data, showing that MAO, FSTL3, and HAPLN1 were significantly upregulated, while PTGFR and RDH11 were downregulated in the IO group. These findings suggest that these five proteins may be involved in the pathogenesis of ovarian inactivity and could serve as biomarkers for early diagnosis and therapeutic targets. This study provides a theoretical foundation for further research on molecular mechanisms and prevention strategies for inactive ovaries in yaks.